[Bug 256681] Incorrect loopback route for aliases IP addresses

From: <bugzilla-noreply_at_freebsd.org>
Date: Fri, 18 Jun 2021 02:52:58 +0000
https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=256681

            Bug ID: 256681
           Summary: Incorrect loopback route for aliases IP addresses
           Product: Base System
           Version: 13.0-STABLE
          Hardware: Any
                OS: Any
            Status: New
          Severity: Affects Some People
          Priority: ---
         Component: kern
          Assignee: bugs_at_FreeBSD.org
          Reporter: zlei.huang_at_gmail.com

Observed this regression on stable/13 and current/14.

Steps to repeat:

# ifconfig tap0 create inet 192.0.2.1/24
# ifconfig tap0 inet 192.0.2.2/32 alias

To verify the route table:

# netstat -4rnW
---------------------------------------
Destination        Gateway            Flags   Nhop#    Mtu      Netif Expire
...
192.0.2.0/24       link#4             U           5   1500       tap0
192.0.2.1          link#4             UHS         6  16384        lo0
192.0.2.2          link#4             UH          7   1500       tap0
...
---------------------------------------

See the loopback route for alias IP address 192.0.2.2 is incorrect.

To verify the impact:
# ping 192.0.2.2
PING 192.0.2.2 (192.0.2.2): 56 data bytes
ping: sendto: No route to host
ping: sendto: No route to host


Expected route table:
192.0.2.2          link#4             UHS         7  16384       lo0

The Mtu should be 16384 and Netif should be lo0. The Flags should contains `S`,
ie. should be same with 192.0.2.1

Expected behavior:
ping alias IP address with success

-- 
You are receiving this mail because:
You are the assignee for the bug.
Received on Fri Jun 18 2021 - 02:52:58 UTC

Original text of this message